Test-Path

Test-Path
    [-Path] <String[]>
    [-Filter <String>]
    [-Include <String[]>]
    [-Exclude <String[]>]
    [-PathType <TestPathType>]
    [-IsValid]
    [-Credential <PSCredential>]
    [-UseTransaction]
    [-OlderThan <DateTime>]
    [-NewerThan <DateTime>]
    [<CommonParameters>]

Test-Path
    -LiteralPath <String[]>
    [-Filter <String>]
    [-Include <String[]>]
    [-Exclude <String[]>]
    [-PathType <TestPathType>]
    [-IsValid]
    [-Credential <PSCredential>]
    [-UseTransaction]
    [-OlderThan <DateTime>]
    [-NewerThan <DateTime>]
    [<CommonParameters>]

The Test-Path cmdlet determines whether all elements of the path exist. It returns $True if all elements exist and $False if any are missing. It can also tell whether the path syntax is valid and whether the path leads to a container or a terminal or leaf element. If the Path is whitespace, then $False is returned. If the Path is an empty string, $null, array of $null or empty array, a non-terminating error is returned.

Test-Path -Path "C:\Documents and Settings\DavidC"

True

This command checks whether all elements in the path exist, that is, the C: directory, the Documents and Settings directory, and the DavidC directory. If any are missing, the cmdlet returns $False. Otherwise, it returns $True.

Test-Path -Path $profile

False

Test-Path -Path $profile -IsValid

True

These commands test the path of the PowerShell profile.

The first command determines whether all elements in the path exist. The second command determines whether the syntax of the path is correct. In this case, the path is $False, but the syntax is correct $True. These commands use $profile, the automatic variable that points to the location for the profile, even if the profile does not exist.

For more information about automatic variables, see about_Automatic_Variables.

Test-Path -Path "C:\CAD\Commercial Buildings\*" -Exclude *.dwg

False

This command checks whether there are any files in the Commercial Buildings directory other than .dwg files.

The command uses the Path parameter to specify the path. Because the path includes a space, the path is enclosed in quotation marks. The asterisk at the end of the path indicates the contents of the Commercial Building directory. With long paths, such as this one, type the first few letters of the path, and then use the TAB key to complete the path.

The command specifies the Exclude parameter to specify files that will be omitted from the evaluation.

In this case, because the directory contains only .dwg files, the result is $False.

Test-Path -Path $profile -PathType leaf

True

This command checks whether the path stored in the $profile variable leads to a file. In this case, because the PowerShell profile is a .ps1 file, the cmdlet returns $True.

These commands use Test-Path with the PowerShell registry provider.

The first command tests whether the registry path of the Microsoft.PowerShell registry key is correct on the system. If PowerShell is installed correctly, the cmdlet returns $True.

Test-Path -Path "HKLM:\Software\Microsoft\PowerShell\1\ShellIds\Microsoft.PowerShell"

True

Test-Path -Path "HKLM:\Software\Microsoft\PowerShell\1\ShellIds\Microsoft.PowerShell\ExecutionPolicy"

False

This command uses the NewerThan dynamic parameter to determine whether the "PowerShell.exe" file on the computer is newer than "July 13, 2009".

The NewerThan parameter works only in file system drives.

Test-Path $pshome\PowerShell.exe -NewerThan "July 13, 2009"

True

The error returned for null, array of null or empty array is a non-terminating error. It can be suppress by using -ErrorAction SilentlyContinue. The following example shows all cases which return the NullPathNotPermitted error.

Test-Path $null
Test-Path $null, $null
Test-Path @()

Test-Path : Cannot bind argument to parameter 'Path' because it is null.
At line:1 char:11
+ Test-Path $null
+           ~~~~~
    + CategoryInfo          : InvalidData: (:) [Test-Path], ParameterBindingValidationException
    + FullyQualifiedErrorId : ParameterArgumentValidationErrorNullNotAllowed,Microsoft.PowerShell.Commands.TestPathCommand

When a whitespace is or empty string in provided for the the -Path parameter, it returns false. The following example show whitespace and empty string.

Test-Path ' '
Test-Path ''

False
Test-Path : Cannot bind argument to parameter 'Path' because it is an empty string.
At line:1 char:11
+ Test-Path ''
+           ~~
    + CategoryInfo          : InvalidData: (:) [Test-Path], ParameterBindingValidationException
    + FullyQualifiedErrorId : ParameterArgumentValidationErrorEmptyStringNotAllowed,Microsoft.PowerShell.Commands.TestPathCommand

This cmdlet supports the common parameters: -Debug, -ErrorAction, -ErrorVariable, -InformationAction, -InformationVariable, -OutBuffer, -OutVariable, -PipelineVariable, -ProgressAction, -Verbose, -WarningAction, and -WarningVariable. For more information, see about_CommonParameters.

You can pipe a string that contains a path, but not a literal path, to this cmdlet.

The cmdlet returns a Boolean value.

The cmdlets that contain the Path noun (the Path cmdlets) work with path names and return the names in a concise format that all PowerShell providers can interpret. They are designed for use in programs and scripts where you want to display all or part of a path name in a particular format. Use them as you would use Dirname, Normpath, Realpath, Join, or other path manipulators.

The Test-Path is designed to work with the data exposed by any provider. To list the providers available in your session, type Get-PSProvider. For more information, see about_Providers.